Clamping device.



W. J. KLEINSTEUBER.

CLAMPING DEVICE.

ATION FILED APPL .1914. 1,155,662. Patented 001:. 5,1915.

Ill/mm 55 4 .nnrrn sin WILLIAM J. KLEINSTEUBER, OF MILWAUKEE, WISCONSIN.

OLAMIING DEVICE.

masses.

Specification of Letters Patent.

Patented Get. 5, 1915.

Application filed August 10, 1914. Serial No. 856,316.

To all whom it may concern.

Be it known that I, VVILLIAM J. KLEIN- srnnenn, a citizen of the UnitedStates, residing at Milwaukee, in the county of Milwaukee and State ofWisconsin, have invented a certain new and useful Improvement inClamping Devices, of which the following is a specification.

This invention relates to improvements in the construction of clampingdevices for elements having screw threaded or similarly roughened outersurfaces, and is especially applicable to devices for clamping studs,bolts and the like.

An object of the invention is to provide a clamping device which issimple in construction and eiiicient in operation.

One of the more specific objects is to provide a clamping deviceespecially applicable for clamping and driving studs, bolts and thelike, in which clamping of the entire outer surface of the portion ofthe element being clamped, is effected.

Another object is to provide a clamping device which will efiectivelyclamp the element without in any way distorting the clamped surfacethereof.

It has heretofore been customary in the driving of studs and the like,to use a socketed cap having a screw threaded socket into which one endof the stud was inserted. The socket was provided with a portion adaptedto receive a wrench or other implement for the application of powerduring the driving operation. It has been found with these priordevices, when the thread of the socketed cap became worn so as toloosely fit the end of a standard stud, that upon the application ofconsiderable driving force, the threads of the stud were distorted so asto necessitate re-cutting of the same in order to permit readyapplication of a standard nut. With the present invention, suchdistortion of the threads is positively prevented and the stud threadseven upon application of the severest driving pressure, are kept intheir natural condition. This result is attained by providing a devicewhich produces clamping of the entire surface of the stud thread, and inwhich an increase in driving force automatically causes a correspondingincrease in the clamping pressure on the stud.

A clear conception of an embodiment of the invention may be had byreferring tothe drawing accompanying and forming a part of thisspecification in which like reference characters designate the same orsimilar parts in the various views.

Figure 1 is a central vertical section through a stud driver showing theclamp mg jaws thereof fully spread. Fig. 2 is a s de elevation of thestud driver, showing a part of the head of the cross bolt broken away.Fig. 3 is an enlarged fragmentary sectional view through the jaws andend plate of a stud driver showing an end of a stud lnserted therein,the jaws being fully separated. Fig. i is an enlarged fragnlentarysectional view through the jaws and end plate of a stud driver showingthe end of a stud clamped firmly between the jaws.

The stud driver as illustrated, comprises essentially a clamping memberor cylindrical socket 1 having a tapered bore in one end thereof andhaving a square driving projection 11 at the other end thereof. Theclamping jaws or jaw members 2 have tapered outer surfaces which closelyfit the tapered bore of the socket 1. The adjacent mid portions of thejaws 2 are screw threaded to receive the end of the element or stud 13which is to be clamped. The jaws 2 are normally held apart so that a gap12 exists between the adjacent surfaces of the aws, by means of helicalcompression spr ngs 8 which are fitted into alined sockets 1n the jaws2.

The end plate 3 which normally coacts with plane surfaces of the jaws 2,has a zone surface adapted to fit the end of a standard stud, when suchstud is screwed lnto position within the jaws 2 preliminarily todriving. The plate 3 is normally held agalnst the plane surfaces of thejaws 2 by means of one or more helical compression springs 9. Theopposite end of the compress on spring 9 may re-act against a plate 10in order to prevent the spring end from entering the gap 12 between thejaws. The cross-bolt 5 closely fits alined bores 1n the jaws 2 andpasses through the recesses 4 in the socket 1. The ends of the bolt 5are provided with antifriction rollers 6 which co-act with cam surfacesformed on the sides of the recesses at. The bolt 5 and jaws 2, as wellas the rollers 6, are removable from the device upon removal of the nut7 which normally holds these elements in place within the socket 1.

In employing the clamping device for i to enter the adjacent threads onthe jaws todriving studs, a stud 13 is first screwed into 7 the jawsocket by hand until it assumes the position as indicated in Fig. 3,with the end of the stud eoacting with the Zone surface of the end plateThe opposite end of the stud is then started into the threaded hole intowhich the stud is to be driven, and a wrench or other driving implementis applied to the driving projection 11. Further screwing of the stud 18into the jaws 2 is prevented by 'means of the spring 9 which augmentsthe friction resisting turning of the stud in the jaws. Upon shiftingthe clamping socket l angularly, the rollers 6 move along the camsurfaces of the recesses 1 and cause the jaws 2 and socket 1 to movelongitudinally relatively to each other,

thereby causing the jaws to approach each other. The relativelongitudinal movement of the jaws and socket is effected by the coactionof the bolt 5 with the rollers 6 and with the jaws 2. As the jaws 2approach each other, the threaded portions thereof approach the adjacentthreaded portion of the stud l3 and eventually assume the positionindicated in Fig. 4.

In order to permit the threads of the stud their fullest extent, the endplate 3 must be permitted to move in a direction longitudinally of thejaws, the spring 9 resisting such movement of the end plate 3 and beingslightly compressed during such movement of the plate 3. It'should benoted that in order to permit such movement of the plate 3 to takeplace, there must be greater frictional resistance between thejaws 2 andthe stud 13 than exists between the jaws 2 and the socket 1. If this isnot the case, rotation of the socket 1 will merely cause the jaws 2 torotate upon the stud, the plate 3 being pushed back in the meantime,compressing the spring 9 until it coacts with the surface of the jawsadjacent the spring side of the plate 3. The amount of frictionalresistance between the stud 13 and jaws 2 and between the jaws 2 andsocket 1,

may be readily adjusted by the use of.

springs 8, 9, of different strengths. It should also be noted that ifthe stud 13 is not permitted to move longitudinally rela tive to thejaws 2 during clamping, the threads on the jaws cannot come intoengagement with the entire thread surfaces of the stud 13, so thatcontinued application of the stud driving pressure will produceexcessive pressure against the ends of the stud threads, thus tending todistort these threads. By permitting the jaws 2 to engage the entiresurfaces of the stud threads, distortion of these threads is positivelyprevented and the threads will readily receive a standard nut uponremoval of the stud driver and without necessitating recutting of thethreads.

In order to remove the stud driver from the end of the stud, it isnecessary onlyto reverse the direction of -'movement of the drivingimplement, when the rollers 6 will travel along the cam surfacesof therecesses it in a reverse direction and the jaws 2 will movelongitudinally relatively to the socket 1 and will be automaticallyseparated by the springs 8. As the studassumes the position indicated inFig. 3 during unelamping, the end plate 3 isagain restored to-its normalposition by the spring 9 and the driver may be readily removed from thestud 13 by hand.

Itwill be noted that anincrease of the driving force willcorrespondinglyincrease the clamping grip of the jaws 2 upon the stud.The formation of the plate 3.with

a zone surface which fits the corresponding end surface. of a standardstud, will protect the end of the stud against distortion which mightotherwise result. VVhile the present disclosure illustrates I a meansfor causing the jaws to approach consisting of a tapered bore in thesocket '1 and correspondingly tapered outer surfaces .of the jaws 2, itis essential only to have some means for causing the jaws 2 to approachparallel to each other in order to secure a firm and uniform grip uponthe stud. The V provision of rollers 6 at the ends of the bolt 5produces an antifriction' means for pulling the jaws 2 into the socketif and will eliminate excessive wear between the parts. It should alsobe noted that the device while disclosed as a stud driver, may beapplied with equal efficiency in a lock nut or other similar device and'Inay also be applied to clamping devices for spindles which haveparallel grooves or ridges instead of screw threads. In any case themeans for permitting longitudinal movement of the element being clampedduring clamping, are essential in order to insure full contact of theclamping jaws against the adjacent surfaces of the element beingclamped. 7

It should be understood that it is not desired to be limited to theexact details of construction shown and described, for obviousmodifications will occur to a person skilled in the art.

It is claimed and desired to secure by Let ters Patent,

1. In a clamping device for screw threaded elements, jaw members havingthreaded portions engageable with'the element to be clamped, and meansfor automatically fore ing said jaw members toward the element uponapplication of rotary force to said forcing means and of rotationopposing resistance to said jaw members. 7 r

2. In a clamping device for screw-threaded elements, jaw membershavingthreaded portions,.means for moving said threaded portions transverselyof and into engagement with the element, and longitudinally movablemeans engaging an end of the element for permitting relativelongitudinal movement of said element and of said jaws during transverseclamping movement of the latter.

3. In a clamping device for screw threaded elements, jaw members havingthreaded portions engageable with the element to be clamped, meansnormally tending to separate said jaw members, and means for auto-'matically forcing said jaw members laterally against the element uponapplication of rotary force to said forcing means and of rotationopposing resistance to said jaw members.

4:. In a clamping device for corrugated elements, jaw members havingcorrugated portions engageable with the element to be clamped, means forforcing said jaw members against the element during clamping, and meansengaging an end of the element, said means permitting relativelongitudinal movement of the element and of at least one of said jawmembers during clamping.

5. In a clamping device for screw-threaded elements, jaw members havingthreaded portions, a clamping member rotatable relatively to said jawmembers to move said threaded portions transversely of and intoengagement with the element, and means for permitting relativelongitudinal movement of said element and of said jaws during transverseclamping movement of the latter.

6. In a clamping device for corrugated elements, jaw members havingcorrugated portions engageable with the element to be clamped, meansnormally tending to separate said jaw members, means for forcing saidjaw members against the element during clamping, and means engaging anend of the element, said means permitting relative longitudinal movementof the element and of at least one of said jaw members during clamping.

7. In a clamping device for screw threaded elements, javv'members havingthreaded portions engageable with the element to be clamped, a clampingmember coacting with said jaw members, said clamping member beingangularly shiftable relative to said jaw members and said jaw membersbeing surfaces of said jaw members upon applica tion of rotary force tosaid clamping member and of rotation opposing resistance to said jawmembers.

9. In a clamping device for corrugated elements, jaw members havingcorrugated portions adapted for engagement with the element to beclamped, means for forcing said .jaw members against the element, andmeans for first preventing and subsequently permitting relativelongitudinal movement of the element and of at least one of said jawmembers during clamping.

10. In a clamping device for screw-threaded elements, jaw members havingwedge surfaces and having threaded portions engageable with the elementto be clamped, a clamping member having surfaces engageable with thewedge surfaces of said jaw members, means for automatically forcing saidclamping member along the wedge surfaces of said jaw members uponapplication of rotary force to said clamping member and of rotationopposing resistance to said jaw members, and a spring-pressed movablestop engaging an end of said element for permitting relativelongitudinal movement of said jaws and of said element during clamping.

In testimony whereof, the signature of the inventor is afiixed hereto inthe presence of two witnesses.

WILLIAM J. KLEINSTEUBER.

Witnesses:

W. H. LIEBER, J. J. KANE.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

' Washington, D. C.

